SAN FRANCISCO and MOUNTAIN VIEW, Calif., Jan. 19, 2000 -- Chevron Corp. and Ariba, Inc.
today announced an agreement to create Petrocosm Marketplace, the first global,
independent internet marketplace to be owned by buyers and suppliers across the energy
industry.

Petrocosm Marketplace is planned to be an open internet marketplace and exchange that will
go live in the second quarter, 2000, at www.petrocosm.com. It intends to offer
browser-based access with internet-hosted procurement to enable companies of all sizes to
buy and sell products and services that span the oil and gas industry supply chain:
drilling, electrical, pipes, valves and fittings; and professional, engineering, and
construction services. This venture is expected to enable companies in the energy industry
to leverage the internet to derive cost savings, new revenue streams and competitive
advantage. Based on independent market research, Petrocosm estimates that net market
electronic trading benefits such as aggregated purchasing, lower transaction costs and
seamless access to larger global markets could drive $11 billion in oil and gas industry
savings and efficiencies.

"The energy industry is being transformed by the internet and business-to-business
(B2B) eCommerce," said Dave O'Reilly, chairman and CEO, Chevron Corp. "Chevron
is playing a very active role in adopting this technology to increase the efficiency of
our business processes."

"Chevron is visionary in its cooperative approach to providing an independent,
efficient trading environment for its industry," said Keith Krach, chairman and CEO
of Ariba. "Chevron also provides an excellent example of how an innovative large
buyer can both save and profit in the new economy by extending its own B2B eCommerce
infrastructure and purchasing power to create an open, scalable, industry net
market."

Petrocosm Marketplace is designed to use the Ariba B2B eCommerce platform, including Ariba
Network commerce services, Ariba ORMS application, Ariba ORMX hosted
service, Ariba IBX marketplace services, and net market and dynamic pricing
solutions and services which Ariba will gain through its pending mergers with TRADEX
Technologies and Trading Dynamics

As eContent manager for Petrocosm, Requisite is expected to utilize its internet-based
eMerge catalog toolset to establish and manage the Petrocosm supplier content. Through the
use of its unified structure, Requisite intends to enable oil and gas industry suppliers
to rapidly develop and manage a high quality, integrated catalog.

"The success of internet marketplaces is dependent on supplier enablement and
effective catalog content management," said Barbara Mowry, president and CEO of
Requisite. "We're delighted to extend our capabilities to help create this exciting
new net marketplace leader for the energy industry."

Petrocosm Corp. is an entrepreneurial, venture-backed company in which Ariba, Chevron and
Crosspoint Venture Partners each have invested to hold minority stakes. The majority of
equity ownership in Petrocosm is expected to be held by energy industry participants of
all sizes. The equity stake for each participant is expected to be based on the amount of
business committed through the internet marketplace, with special consideration for those
who commit sooner. Ariba is also expected to receive revenues based on a percentage of
transaction-based network revenue streams.

"We believe neutrality is an important success factor for industry trading
exchanges," said Bruce Richardson, senior vice president of research for Boston-based
AMR Research. "In the case of Petrocosm, not only has a new independent company been
created, but the players have taken the concept of neutrality further by creating an
equity structure that encourages industry ownership and broad participation from both
buyers and suppliers. Not only is there an equity play for participants, but they can also
benefit from the efficiencies created by such exchanges. For buyers, for example, we
estimate savings potential from 5 percent to as much as 30 percent of spending."

"Participants can broadly share in the economies of scale, market efficiencies, and
equity created by Petrocosm," said Don Paul, vice president, technology, for Chevron.
"We believe this company-neutral approach -- with an entrepreneurial management team
and experienced venture capital backing -- is critical to the broad adoption and ultimate
success of this marketplace."

The marketplace is expected to include rationalized, energy industry-specific catalogs
with millions of items together with services for supplier enablement, hosted and
enterprise e-procurement for goods and services, auctions, reverse auctions, bid/ask
exchanges, strategic sourcing, spot buying, customer-specific pricing, electronic
payments, logistics, integration to ERP systems and online community forums.

Application of this type of technology has been discussed at the American Petroleum
Institute's Petroleum Industry Data Exchange (PIDX). "We are pleased to see
activities that leverage B2B technology to benefit energy industry buyers and sellers, an
objective of PIDX, the eCommerce committee of the API," said Kendra Martin, director
of eBusiness for API.

Chevron, a San Francisco-based company with $30 billion in annual revenues and $60 billion
market capitalization, intends to help initiate the net market's transactional liquidity
by targeting a substantial portion of its annual $10 billion in spending through
Petrocosm.

Further, to accelerate deployment and time-to-benefit for all participants, Chevron and
Ariba will leverage components of the Ariba procurement solution that is already fully
functional in Chevron's Bakersfield, Calif. operations. This Ariba implementation has been
enhanced since early 1999 to support energy industry requirements, including
industry-specific supplier catalog content, and is now capturing 90 percent of the
business unit's annual materials purchasing.

"We've been pleased with the robustness and scalability of the Ariba solution,"
said Paul. "That's why we are currently extending the same Ariba solution to our
operations in the Gulf of Mexico."

Infrastructure hardware, software and services for Petrocosm are expected to be provided
by Hewlett-Packard Company.

Crosspoint Venture Partners is the leading venture capital firm in the B2B eCommerce
market with over 40 current investments in this sector.

About Ariba, Inc.

Ariba, Inc. is the leading provider of business-to-business eCommerce services and
solutions to leading companies around the world, including 15 of the Fortune 100. The
company delivers an open, end-to-end, best-of-breed platform of interoperable solutions to
manage corporate purchasing on the Internet, build net markets, and provide suppliers with
buyer access and integration. Together, Ariba's software and services leverage the
Internet-based Ariba Network to integrate the internal and external commerce processes of
buyers, suppliers, net markets and commerce service providers. The result is a global
eCommerce infrastructure that provides cost saving and revenue opportunities for
businesses of all sizes. Ariba can be contacted in the U.S. at +1.650.930.6200 or at
www.ariba.com.

About Chevron Corp.

Chevron, headquartered in San Francisco, California, is a leading energy and chemical
company, operating in about 90 countries through its 500 subsidiaries, partnerships,
affiliates, and other entities. Chevron employs about 31,000 people worldwide.

Ariba is a registered trademark and Ariba Network is a trademark of Ariba,
Inc. This press release contains forward-looking statements relating to the matters set
forth herein that are based on current expectations, estimates and projections. Words such
as "will," "expects," "intends," "plans,"
projects," "believes," "estimates" and similar expressions are
used to identify such forward-looking statements. These statements are not guarantees of
future performance and involve certain risks, uncertainties and assumptions that are
difficult to predict. Therefore, actual outcomes and results may differ materially from
what is expressed or forecasted in such forward-looking statements.

Among the factors that could cause actual results at Petrocosm to differ materially are:
(i) Petrocosm was recently formed and is at an early stage of development; (ii) the level
of participation of oil and gas companies in the Petrocosm Marketplace; (iii) the
company's success in attracting a management team; (iv) the effectiveness of the company's
Internet-based eCommerce platform; (v) the company's ability to implement its business
plan; (vi) factors and risks which adversely affect key participants in Petrocosm; and
(vii) the attractiveness and the offerings of other competitors in this market. In
addition, Petrocosm could be affected by general domestic and international economic and
political conditions.

Numerous factors and risks could adversely affect Ariba. Some of the factors and risks
associated with Ariba's business are discussed in its registration statement on Form S-1
declared effective by the Securities and Exchange Commission ("SEC") on June 22,
1999, its Annual Report on Form 10-K for the year ended September 30, 1999 filed with the
SEC and in the other reports filed by it from time to time with the SEC.

HOUSTON, March 23, 2000 -- Petrocosm Corp. today announced that Texaco Inc. has joined
Petrocosm marketplace as a founding member of the first, global Internet marketplace
created and owned by the energy industry.

Petrocosm also announced the appointment of Norman C. Chambers, currently senior vice
president of Halliburton Company, as its chief executive officer. The appointment is
effective April 3.

The Petrocosm marketplace, first announced Jan. 19, will launch in the second quarter
at www.petrocosm.com. It will offer an open marketplace for companies of all sizes to buy
and sell products and services that span the petroleum industry supply chain: drilling
equipment, electrical supplies, pipes, valves and fittings, as well as professional,
engineering and construction services. Companies in the energy industry will be able to
leverage this Internet marketplace to achieve cost savings and generate new revenue
streams, ultimately gaining a competitive advantage.

"Our equity participation in the Petrocosm marketplace is a highlight in Texaco's
growing portfolio of strategic e-business alliances," said Gregory M. Vesey, vice
president, E-Business for Texaco. "We're very excited to join this venture as it
finalizes preparations to go live."

Vesey continued, "The new business model behind Petrocosm will transform the
traditional customer/supplier relationship by creating a limitless marketplace that can be
easily accessed by both the largest and smallest companies around the globe. This open,
independent model will provide significant opportunities for cost savings and increased
market efficiencies for buyers and sellers - key objectives in Texaco's e-business
strategy."

"Ever since the creation of Petrocosm marketplace two months ago, we've seen
tremendous interest from players in every part of the energy supply chain," said new
Petrocosm CEO Norman Chambers. "We're very pleased to welcome Texaco as a founding
partner with Chevron, Ariba and Crosspoint Venture Partners."

"We look forward to working with Texaco and value their early recognition and
understanding of the rewards this marketplace can bring to the energy industry."

Chambers, 51, previously served as president of Halliburton Energy Development, which
integrated the development and production of oil and gas fields in partnership with
Halliburton's customers. With more than 25 years experience in the upstream and midstream
of the oil and gas industry, Chambers has been involved with technology teams at
Halliburton and Brown & Root and held a number of operational and senior management
positions.

Chambers was graduated from Springfield College in 1971 with a bachelor of arts degree.
In 1982, he was graduated with distinction from Boston College with a master of business
administration degree. He also has attended the Tufts University Fletcher School of Law
and Diplomacy and Harvard Business School.

Petrocosm will be headquartered in Houston, Texas. Interested parties can obtain more
information by dialing 1+(877) 627-9796.